How to Collect Suspect Samples of Laurel Wilt Disease

Information extracted from UF/IFAS Extension

FEE: $75

Woody plants in the laurel family (Lauraceae) affected by laurel wilt disease typically have wilted leaves and a black or dark discoloration in the outer sapwood of the main stem or branches. To confirm presence of the laurel wilt pathogen, this discolored sapwood should be collected for analysis. Evidence of ambrosia beetle attack may or may not be present.

If you suspect a plant has laurel wilt disease and would like confirmation of the causal pathogen, please follow these steps to submit a plant sample:

1. Type of sample:

A. If collecting from the main stem of a mature tree: Using a hatchet, hammer & chisel, or knife, remove the bark down to the surface of the sapwood (xylem) and look for discoloration in the wood. Chisel or cut out a few thick chips of the discolored wood.

B. If collecting from small stems or branches with wilted leaves: With a knife, remove bark down to the surface of the sapwood and look for discoloration in the wood. Cut and collect a few short branches or stem sections that contain this discoloration. Small twigs that have been dead a long time and are dry and crispy when broken are not good samples for pathogen confirmation

2. Fill out the sample submission form with information about the sample (type of plant, date collected, exact location of diseased plant, symptoms observed, your name, address and contact information).

3. Put the plant material in a plastic zip-lock bag and the sample submission form in another plastic zip-lock bag. Put all these bags into another bag to keep them together. Tightly seal all bags to prevent the possibility of live insects in the wood from escaping.

4. If you have digital photos of the plant, particularly the damaged portions, from which you took the sample, they can be helpful in deciding how to treat the sample. Please send these photos to trec-pdc@ifas.ufl.edu.

5. Secure the samples in a sturdy box and write “laurel wilt samples” clearly on the outside.

6. Send samples preferably by overnight mail early in the week so they can be quickly processed and don’t sit over the weekend.